Supplementary AnalysesPropensity score weighted regressions. Dominant CEOs may select CFOs who have strong desires to affiliate with and ingratiate CEOs. Meanwhile, these CEOs are more likely to undertake intensive M&A activities. In other words, CEO-CFO dyads with different levels of LSM are not randomly assigned across firms. To mitigate bias from the non-random assignment of CEO-CFO LSM, we conduct additional analyses using the inverse-probability-of-treatment-weighted (IPTW) methodology—a two-stage selection-on-observables estimation technique (Robins, Hernan, & Brumback, 2000). IPTW has been used in prior observational research to mitigate selection bias and adjust for non-random treatment (Almandoz & Tilcsik, 2016; Yue, Luo, & Ingram, 2013). This weighting approach is akin to simulating what would occur if all firms have both high and low levels of CEO-CFO LSM, addressing the possibility that specific types of firms have a high level of LSM.